Mump 0812 13 Z 1966 Shelby Gt350 Timing Gear

The original timing chain and gear was replaced at some point during the engine's life, which is not surprising. Contrary to popular belief, 289 High Performance engines did not have a dual-roller timing set or iron cam gear. They had a conventional silent chain setup with a nylon-coated aluminum cam gear, which was replaced at some point with this aftermarket iron gear timing set.